Subtract 21/81 from 7/4
1st number: 1 3/4, 2nd number: 21/81
7/4 - 21/81 is 161/108.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 81 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 4 × 81 = 324,
7/4 = 7 × 81/4 × 81 = 567/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
21/81 = 21 × 4/81 × 4 = 84/324 - Subtract the two like fractions:
567/324 - 84/324 = 567 - 84/324 = 483/324 - After reducing the fraction, the answer is 161/108
- In mixed form: 153/108
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